MATLAB: Does DAQHWINFO list different devices for ANALOGINPUT and ANALOGOUTPUT even though they have the same device ID for the Data Acquisition Toolbox

analoganaloginputanalogoutputcarddaqhwinfoData Acquisition Toolboxdevicedifferentidsound

Why does DAQHWINFO list different devices for ANALOGINPUT and ANALOGOUTPUT even though they have the same device ID for the Data Acquisition Toolbox?
If I have two or more soundcards and any of the soundcards has more input devices than output devices, the information returned does not necessarily match what is in the machine.
For example, if I have a sound card with three input devices and two output devices and another card with one input and one output device (this is the case with the Delta-44 24-bit sound card installed in a computer with any other normal sound card), the constructor list will look like:
 { '24-bit AI 1'  '24-bit AO 1'                                             
   '24-bit AI 2'  '24-bit AO 2'                                            
   '24-bit AI 3'  '16-bit AO 1'                                            
   '16-bit AI 1'  '' }
It should look like:
 { '24-bit AI 1'  '24-bit AO 1'                                             
   '24-bit AI 2'  '24-bit AO 2'                                            
   '24-bit AI 3'  ''                                                       
   '16-bit AI 1'  '16-bit AO 1' }

Best Answer

This enhancement has been incorporated in Release 2012a (R2012a). For previous product releases, read below for any possible workarounds:
This has been verified as a bug in Data Acquisition Toolbox 2.2 (R13) in the way that DAQHWINFO handles a device without both analog input and output channels.
Currently, to work around this issue, try downloading a modified DAQHWINFO from MATLAB Central:
http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=3261&objectType=file
Note that MathWorks does not guarantee or warrant the use or content of these submissions. Any questions, issues, or complaints should be directed to the contributing author.
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